GeoGebra sounds like something that would work, although I only really use it for graphing so I couldn't tell you a lot about the other features. People make some
really cool stuff with it though.
I like it a lot for graphing trig stuff though, 10/10 if you like some dank functions
As for worksheets, GeoGebra includes its own kind of
worksheets, although they're not really the printable type. If you intend to write SAC or Exam style stuff, I'd actually just go with LaTeX, or if you hate yourself a little bit (or you're just lazy), Word's equation editor will work well enough for most things. There's also a
Mathematics Add-in for Word that you can use to make graphs in the document, but honestly they look kinda gross imo and it doesn't make entering equations any less annoying.
LaTeX is pretty good, but a bit inconvenient for writing equations (but it looks really great imo). You can try it out here on AN by doing the following:
[tex]\int \sin \left (x+\frac{pi}{3}\right ) dx[/tex]
 dx)
Or you can generate it a little easier using
this, which lets you save as a few image types. If LaTeX is something that interests you, try checking out
ShareLaTeX. Learning curve's a bit steep but it's worth it imo.